1. Field of the Invention
The present invention relates generally to the field of work machines. It relates more particularly to work machines with hydraulic systems.
2. Description of the Related Art
Off highway vehicles include construction equipment such as a backhoe loader, also called a loader backhoe, or shortened to “backhoe” within the common language of the industry, is a vehicle that includes a tractor like unit fitted with a bucket loader on the front and a backhoe on the back. Due to its size and versatility, backhoe loaders are very commonly used in agricultural pursuits as well as construction projects. The backhoe loader is also known as a TLB (Tractor-Loader-Backhoe), which is to say, a tractor fitted with a front loader and a rear backhoe attachment.
Backhoe loaders are very common and can be used for a wide variety of tasks such as: construction, small demolitions, the transportation of building materials, powering a variety of building equipment, digging holes/excavation, landscaping, breaking asphalt, and paving roads. Advantageously, the backhoe bucket can also be replaced with a variety of attachments including powered attachments such as a grapple, an auger, or a stump grinder.
The relatively small frame and precise control make backhoe-loaders very useful in areas that are too small for larger equipment. Their versatility and compact size makes them one of the most popular urban construction vehicles. For larger projects, a tracked excavator is generally used.
Vehicles, such as those used in the agricultural, forestry and construction industries are typically controlled by an operator sitting at an operator station. In the operation of the equipment there may be times in which the engine is set to run at a throttle speed that is unneeded when operations cease or are limited. For example, a backhoe may be used to dig a trench and while the operator is waiting for a depth check of the trench, the controls are not being directed to do any work so the operator manually reduces the engine speed to idle, to thereby reduce fuel consumption.
What is needed in the art is a control system that allows precise, reliable, detection of loads on the engine and controls an auto-idle feature without adding new sensors to the system.